Inhliziyo

Inhliziyo iyisitho semisipha ezilwaneni eziningi, esimpompa igazi ngemithambo yegazi yohlelo lokujikeleza kwegazi.Igazi elimpontshwayo lithwala umoya-mpilo nezakhi zomzimba emzimbeni, ngenkathi lithwala imfucumfucu ye-metabolic efana ne-carbon dioxide emaphashini. Kubantu, inhliziyo icishe ilingane nenqindi evaliwe futhi itholakala phakathi kwamaphaphu, egumbini eliphakathi kwesifuba.

Indlela yayo yokusebenza

Inhliziyo impompa igazi ngesigqi esinqunywa yiqembu lamaseli okwenza amandla ku-sinoatrial node. Lokhu kukhiqiza umsinga wamanje obangela ukusikwa kwenhliziyo, kudlule endaweni engeyokuqala futhi kuhambisane nohlelo lokuqhuba kwenhliziyo. Inhliziyo ithola igazi elinomoya-mpilo ophansi kusuka ekujikelezeni kwesistimu, okungena ku-atrium elungile kusuka ku-venae cavae ephezulu futhi engaphansi futhi kudlulele ku-ventricle efanele. Kusuka lapha kudonswa ekuhambeni kwegazi, ngamaphaphu lapho ithola khona umoya-mpilo futhi ikhiphe isikhutha. Igazi elinomoya-mpilo bese libuyela e-atrium engakwesobunxele, lidlule ku-ventricle engakwesokunxele bese likhishwa nge-aorta liye ekujikelezeni kwesistimu − lapho i-oxygen isetshenziswa khona futhi ihlanganiswe ne-carbon dioxide. Inhliziyo ishaya ngesilinganiso sokuphumula esiseduze kwezingu-72 ngomzuzu. Ukuvivinya umzimba kukhuphula izinga okwesikhashana, kodwa kwehlisa ukuphumula kwenhliziyo esikhathini eside, futhi kuhle empilweni yenhliziyo.

Isakhiwo

Inhliziyo yomuntu itholakala maphakathi ne-mediastinum, ezingeni le-vertebrae ye-thoracic T5-T8. Isaka elinezimbili elibizwa ngokuthi i-pericardium lizungeze inhliziyo futhi linamathele ku-mediastinum. Ingxenye engemuva yenhliziyo ilele eduze kwekholomu ye-vertebral, kanti ingaphambili langaphambili lihlala ngemuva kwe-sternum nezimbambo.] Ingxenye engenhla yenhliziyo okunamathiselwe kwemithambo yegazi emikhulu eminingana — i-venae cavae, i-aorta nesiqu samaphaphu. Ingxenye engenhla yenhliziyo isezingeni le-cartilage yesithathu ebizayo. Ithiphu engezansi yenhliziyo, isihloko, ilele ngakwesobunxele se-sternum (8 kuya ku-9 cm ukusuka kulayini ophakathi) phakathi komgwaqo wesine nezimbambo zesihlanu eziseduze nokukhuluma kwazo noqwanga olubizayo.

Ingxenye enkulu kunazo zonke yenhliziyo ivame ukubekelwa eceleni kancane kwesokunxele sesifuba (noma kwesinye isikhathi ingase isuswe ngakwesokunene) futhi izwakale ingakwesobunxele ngoba inhliziyo yangakwesokunxele inamandla futhi inkulu, ngoba ipompa kubo bonke izitho Zomzimba. Ngoba inhliziyo iphakathi kwamaphaphu, iphaphu langakwesobunxele lincane kunephaphu elifanele futhi linenothi yenhliziyo emngceleni walo ukwamukela inhliziyo. Inhliziyo imise okwengqamuzana, isisekelo sayo sibheke phezulu futhi sehlelela phezulu.Inhliziyo yabantu abadala inesisindo esingama-250-350 amagremu (9-12 oz) .Inhliziyo ivame ukuchazwa njengosayizi wenqindi: cm (5 in) ubude, 8 cm (3.5 in) ububanzi, no-6 cm (2.5 in) ngobukhulu, yize le ncazelo iphikiswa, ngoba inhliziyo kungenzeka ibe nkudlwana. Abasubathi abaqeqeshwe kahle bangaba nokukhulu kakhulu izinhliziyo ngenxa yemiphumela yokuvivinya umzimba esicutshini senhliziyo, esifana nokuphendula kwemisipha yamathambo.